Dendrographa decolorans  

Thallus thin, white to lilac- to pinkish grey, becoming grey to brownish grey in the herbarium, ± rimose; a grey-black prothallus often present. Soralia punctiform when young, spreading and becoming confluent, mauve grey to pale lilac-grey, occasionally with an ochre tinge.
Conidiomata pycnidia, rare. Conidia 6-7 × ca 2 µm, bacilliform, straight to slightly curved, 1-septate, hyaline to pale olive-brown.
Teleomorph: ascomata apothecia, rare, elongate to circular, 0.5-1.3 mm diameter, the disc convex, persistently pruinose. Ascospores 30-37 × 4-5 um, fusiform, curved.
Chemistry: thallus C–, K–, KC–, Pd–, UV– (unidentified fatty acids).